Rotary shear valve assembly with hard-on-hard seal surfaces

ABSTRACT

A multi-position rotary shear valve assembly having a substantially metallic or ceramic stator device and a substantially metallic or ceramic rotor device. The stator device defines a substantially planar stator face and at least two or more stator channels in fluid communication with the stator face at corresponding stator ports, while the rotor device includes a substantially planar rotor face defining one or more rotor channels. A tribological coating is disposed atop at least one of the rotor face and the stator face, which enables a substantially fluid-tight, selective relative rotation between the rotor face and the stator face, at a rotor-stator interface, between two or more rotor positions.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119(e) from co-pendingU.S. Provisional Patent Application Nos. 61/225,143, filed Jul. 13,2009; 61/301,516, filed Feb. 4, 2010; and 61/328,594, filed Apr. 27,2010, all of which are entitled “ROTARY SHEAR VALVE ASSEMBLY WITHHARD-ON-HARD SEAL SURFACES”, and naming Tower as the inventor, and allof which are incorporated by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to rotary shear valves, and moreparticularly, relates to shear valves that incorporate hard-on-hardsealing surfaces.

BACKGROUND OF THE INVENTION

Current high pressure liquid chromatography shear valves typicallyemploy a metallic element and a rotor device composed of a polymermaterial that forms fluid-tight seal at a rotor/stator interface. Whilethis combination has been found to be successful, it is limited inpressure rating and valve lifetime. For example, applications requiringhigh pressures above 15 Kpsi and a lifetime greater than about 10Kcycles are not consistently attainable and sustainable using thiscombination.

Accordingly, it is desirable to provide a shear face valve capable ofholding pressures greater than about 15 Kpsi that have expected valvelifetimes greater than 50K cycles.

SUMMARY OF THE INVENTION

The present invention provides a rotary shear valve assembly including astator device that defines a substantially planar stator face and atleast two or more stator channels in fluid communication with statorface at corresponding stator ports. The stator face is composed of asubstantially metallic or ceramic material. The valve assembly alsoincludes a rotor device that includes a substantially planar rotor facedefining one or more rotor channels. The rotor face, similarly iscomposed of a substantially metallic or ceramic material. In accordancewith the present invention, the valve assembly includes a tribologicalcoating disposed atop at least one of the rotor face and the statorface. The rotor device is rotatably mounted about a rotational axis in amanner enabling fluid-tight, selective relative rotation between therotor face and the stator face, at a rotor-stator interface, between twoor more rotor positions.

Accordingly, through the application of a tribological coating, ametal-on-metal stator device/rotor device can be implemented for highfluid pressure applications (i.e., 15 Kpsi to about 25 Kpsi). Hence, notonly can a fluid-tight seal at the rotor/stator interface be maintained,but the valve is are also capable of sustaining high lifecycle capacity(i.e., at least about 75K cycles). Moreover, such a tribological coatingfurther functions to reduce the friction between these two opposed,contacting faces.

In one aspect of the present invention, the tribological coating isprovided by a Diamond Like Coating (DLC).

In another specific configuration the tribological coating is disposedatop the stator face.

In still another specific embodiment, the rotor face and the stator faceis composed of a metallic material such as steel or titanium.

In another aspect of the present invention, the rotor device includes ametallic rotor element containing the substantially planar rotor face.The valve assembly further includes a compliance assembly thatcooperates with the rotor device in a manner orienting the substantiallyplanar rotor face substantially parallel to and substantially flushagainst the substantially planar stator face of the stator device.

In one specific embodiment, the rotor device defines a proximal facingcontact surface oriented opposite the rotor face, and the complianceassembly includes a compliant element in supportive abutting contactwith the contact surface of the rotor device.

Another specific arrangement provides a rotor assembly that includes avalve shaft, configured for rotation about a rotational axis of thevalve assembly, and a head portion disposed at a distal end of the valveshaft. The head portion defines a distal seating surface thereof. Thecompliant element defines a proximal facing surface oriented oppositethe contact surface. The compliant element is disposed between, and inabutting contact with, the contact surface of the rotor device and thedistal seating surface of the head portion.

In still another specific embodiment, the compliant element defines areceiving socket, a bottom portion of which is defined by the seatingsurface. The receiving socket is formed and dimensioned for aligned,sliding axial receipt of a rotor element of the rotor device therein.The receiving socket is further defined by an interior sidewall, formedand dimensioned for press-fit receipt and contact with an outercircumferential wall of the rotor element.

In yet another embodiment, the interior sidewall and the rotor outercircumferential wall cooperate for keyed alignment therebetween. Morespecifically, the interior sidewall and the rotor outer circumferentialwall are D-shaped.

Still another specific configuration provides a rotor assembly thatincludes a valve shaft, configured for rotation about a rotational axisof the valve assembly, and a head portion disposed at a distal end ofthe valve shaft. The compliance assembly includes a ball bearing memberdisposed between the head portion of the rotor assembly and the rotorelement, enabling minute compliant pivotal motion of the rotor faceabout the ball bearing member.

Yet another embodiment provides a head portion having a distal seatingsurface that defines a dome-shaped socket that is formed and dimensionedfor receipt of a portion the ball bearing member therein. The rotorelement having a proximal facing contact surface oriented opposite therotor face, the contact surface defining a dome-shaped ball socketformed and dimensioned for pivotal receipt of another portion the ballbearing member therein.

In this configuration, the compliance assembly further includes a drivering disposed adjacent the seating surface of the head portion. Thedrive ring includes an interior wall that defines a centralthrough-passage formed and dimensioned for axial sliding receipt of therotor element therein. The tolerance is such that minute pivotalmovement atop the ball bearing member is permitted.

In one specific embodiment, the compliance assembly further includes analignment structure configured for aligned cooperation between the rotorelement and drive ring. The rotor element includes a substantiallycylindrical sidewall extending between the rotor face and the contactsurface. The sidewall defines two or more elongated receiving slotsoriented substantially parallel to the rotational axis, and axiallyextending from about a central portion of the sidewall to the contactsurface. The alignment structure includes two or more correspondingguide pins extending radially inward from the interior wall of the drivering. The guide pins being sized and dimensioned for sliding axialreceipt in a corresponding receiving slot.

In another aspect of the present invention, a rotary shear valveassembly is provided having a metallic stator device that defines asubstantially planar stator face and at least two or more statorchannels in fluid communication with stator face at corresponding statorports. A rotor device is also included having a metallic rotor elementthat defines a substantially planar rotor face. The valve assemblyfurther includes a compliance assembly that cooperates with the rotorelement in a manner orienting the substantially planar rotor facesubstantially parallel to and substantially flush against thesubstantially planar stator face of the stator device. Such complianceenables fluid-tight, selective relative rotation between the rotor faceand the stator face, at a rotor-stator interface, at two or more rotorpositions.

BRIEF DESCRIPTION OF THE DRAWINGS

The assembly of the present invention has other objects and features ofadvantage which will be more readily apparent from the followingdescription of the best mode of carrying out the invention and theappended claims, when taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a top perspective view of a micro-fluidic valve assembly thatincorporates both a metallic rotor element and a metallic stator elementdesigned in accordance with the present invention.

FIG. 2 is a bottom perspective view of the micro-fluidic valve assemblyof FIG. 1.

FIG. 3 is a top perspective view of the micro-fluidic valve assembly ofFIG. 1, illustrating the rotor element with a stator ring and statorelement removed.

FIG. 4 is a side perspective view of the micro-fluidic valve assembly ofFIG. 1, illustrated with the stator ring removed.

FIG. 5 is an exploded, top perspective view of a rotor assembly and thestator element of the micro-fluidic valve assembly of FIG. 1.

FIG. 5 is an exploded, top perspective view of a rotor assembly and thestator element of the micro-fluidic valve assembly of FIG. 1.

FIG. 6 is an enlarged, top perspective view of the rotor assembly ofFIG. 5.

FIG. 7 is a partially exploded, top perspective view of the rotorassembly of

FIG. 6, incorporating a compliance assembly constructed in accordancewith the present invention.

FIG. 8 is a reduced, exploded, bottom perspective view of themicro-fluidic valve assembly of FIG. 1.

FIG. 9 is a top perspective view of the rotor assembly incorporating analternative embodiment compliance assembly.

FIG. 10 is a partially exploded, top perspective view of the rotorassembly and compliance assembly of FIG. 9.

FIG. 11 is an exploded, top perspective view of the rotor assembly andcompliance assembly of FIG. 9, together with the stator element.

FIG. 12 is an exploded, bottom perspective view of the rotor assemblyand compliance assembly of FIG. 10.

FIG. 13 is an enlarged, fragmentary, side elevation view, incross-section, of the micro-fluidic valve assembly of FIG. 1,incorporating the compliance assembly of FIG. 9.

FIG. 14 is a side elevation view, in cross-section, of the complianceassembly of FIG. 13.

FIG. 15 is a top perspective view of the rotor assembly incorporatinganother alternative embodiment compliance assembly.

FIG. 16 is an exploded, top perspective view of the rotor assembly andcompliance assembly of FIG. 15.

FIG. 17 is an exploded, bottom perspective view of the rotor assemblyand compliance assembly of FIG. 15.

FIG. 18 is a side elevation view, in cross-section, of the rotorassembly and compliance assembly of FIG. 15.

FIG. 19 is a side elevation view, in cross-section, of the micro-fluidicvalve assembly of FIG. 1, incorporating the compliance assembly of FIG.15.

FIG. 20 is a partially exploded, side perspective view of the rotorassembly and compliance assembly of FIG. 15.

FIG. 21 is an exploded, bottom perspective view of the rotor assemblyand compliance assembly of FIG. 15.

FIG. 22 is an enlarged, exploded, bottom perspective view of thecompliance assembly of FIG. 15.

FIG. 23 is an enlarged, exploded, top perspective view of the complianceassembly of FIG. 15.

FIG. 24 is an enlarged, top plan view of the compliance assembly of FIG.15.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention will be described with reference to a fewspecific embodiments, the description is illustrative of the inventionand is not to be construed as limiting the invention. Variousmodifications to the present invention can be made to the preferredembodiments by those skilled in the art without departing from the truespirit and scope of the invention as defined by the appended claims. Itwill be noted here that for a better understanding, like components aredesignated by like reference numerals throughout the various figures.

Referring now generally to FIGS. 1-8, a rotary shear valve assembly 20is provided that includes a stator device 21 having a substantiallymetallic or ceramic, substantially planar stator face 22. The statordevice defines at least two or more stator channels in fluidcommunication with stator face at corresponding stator ports 23. Thevalve assembly 20 further includes a rotor device 25 having asubstantially metallic or ceramic, substantially planar rotor face 26.In accordance with the present invention, a tribological coating isdisposed atop at least one of the rotor face and the stator face. Thus,when the rotor device 25 is rotatably mounted about a rotational axisfor selective relative rotation between the rotor face and the statorface, at a rotor-stator interface, a fluid-tight seal is formed betweenthe two metallic faces during relative rotation between two or morerotor positions.

Accordingly, due in part to the tribological coating, a metal-on-metalfluid-tight seal is formed at the rotor/stator interface for highpressure applications (i.e., 15 Kpsi to about 25 Kpsi) that is alsocapable of sustaining high lifecycle capacity (i.e., at least about 75Kcycles). Such a tribological coating on at least one of the rotor faceand/or stator face enables the formation of a durable fluid-tight andlow friction seal under the necessary high pressure compressivepressures between the stator device and the rotor device.

As will be described, at least the rotor face 26 and the stator face 22are both composed of a relatively rigid material for increaseddurability under high compression forces. In other configurations, theentire rotor device 25 and the stator device 21 is composed of asubstantially rigid material.

Preferably, both the rotor device and the stator device are comprised ofmetallic compositions such as 316 Stainless Steel, Duplex StainlessSteel, titanium, Alloy Steels or Tool Steel compositions. Other suitablerigid materials, however, have been found that yield similar highpressure ability together with a high lifecycle capacity can be applied,as long as a suitable tribological coating is disposed atop at least oneof the rotor face 26 and/or the stator face 22. One such suitablematerial family is ceramics, for instance, such as Alumina, SSIC,Zirconia. It will be appreciated, however, that whether the rotor andstator is composed of a metal or a ceramic material, that material mustbe capable of being coated with the tribological material.

Coating of at least one of the stator face and/or the rotor face hasbeen found necessary in these high pressure applications in order toform a fluid-tight, low friction seal at the rotor/stator interface. Dueto the substantially rigid material composition of the rotor face andthe stator face, for the aforementioned desired reasons, these rigidmaterials are of course relatively non-compliable.

Such a coating, however, must also exhibit sufficient structuralintegrity for a high lifecycle under these high fluid pressure, highcompressive force conditions. One such suitable and effective coatingfor pressurized fluid-tight seal formation between opposed rigid surfaceinterfaces, under these conditions, is the tribological coatings. Thesecoatings have been found to exhibit high strength (toughness) and lowfriction, as well as being resistant to most chemicals used in LiquidChromatography.

One specific tribological coating that is particularly suitable for thisapplication is the Diamond Like Coatings (DLC), such as the STAR® DLCand BALINIT® DLC provided by Balzers Oerlikon or the aDLC provided byIonbond. Other tribological coatings that exhibit these characteristics,however, can be applied.

In accordance with the present invention, at least one of, or both, thestator face and the rotor face 26 is coated with the tribologicalmaterial. In one specific embodiment, in certain conditions, applyingthe tribological coating to the stator face 22 of the stator boss 27 hasbeen found particularly advantageous to provide a stronger, longerlasting fluid-tight seal at the rotor-stator interface (FIG. 8). Forexample, for high fluid pressure applications (i.e., greater than about18 Kpsi, higher axial compression forces between the rotor face 26 andstator face 22 are necessary to maintain a fluid-tight seal. When thevalve is set (i.e., when the pressure adjuster nut is adjusted until arate of decay is achieved, typically this rate is 0.3 uL/min. Fluidpressure is applied to the valve through the stator port(s) rotor sealgroove(s). Once the valve holds the required amount of pressure (15-25Kpsi in this instance) at the 0.3 uL/min leak rate, the valve is “set”),the high pressure applied to the seal by a spring assembly 30 (thatincludes an adjuster nut 31 and spring washers 32 (FIG. 8)) occasionallycauses the coating seal to be indented by the circumferential edgeportion of the stator boss 27. Thus, if the rotor face 26 is coated(e.g., the rotor face alone or in combination with the stator face),inconsistent results and damage components have been observed in theseinstances due to cracking of the coating, or delaminating at the edgeportion as the valve is actuated.

It is believed that this indentation causes the coating to “flake-off”or delaminate from the rotor seal in the area of the indentation as thevalve is actuated. As this coating is removed, the debris, and possiblythe uncoated metal, has been observed to score the remaining coating,degrading the integrity of the coating on the stator boss, and causingthe coating on the stator to fail. Once this degradation commences, thefluid-tight seal at the rotor/stator interface will fail in holdingpressure.

When only the stator face is coated with the tribological coating, underthese high pressure applications, this degradation is not observed. Itwill further be noted that at lower pressures (3-6 Kpsi), it is believedthat both the stator and rotor seal could be coated (DLC or otherwise)and provide a good seal, since hard-on-hard valves work at thesepressures. Since these pressures applied to the seal would be lower, therotor seal is less likely to be indented and cause the coating to fail.

Referring now to FIGS. 1-5 and 8, a typical shear valve assembly 20 isshown and described. Briefly, as best illustrated in FIG. 8, the shearvalve assembly typically includes a housing assembly 33 (essentiallycomprised of a valve housing and a stator ring) upon which a rotorassembly 29 is rotatably disposed therein. The rotor assembly 29includes a drive shaft 35 and a distally disposed head assembly 36 thatis configured to seat the rotor device 25 thereon. To promote forceconcentration and the ability of the rotor device to pivot atop the headassembly 36, the head assembly includes a raised platform or pad 34upstanding slightly from a distal surface 38 thereof. This upstandingshaft pad 34 is preferably disk-shaped, having a substantially planarseating surface 39 that is configured to seat directly against a contactsurface 40 of the rotor device 25. It will be appreciated, however, thatFIGS. 5, 7 and 8 are illustrated with a thin compliant element or shimmember 44 disposed there between which will be described in detailbelow.

The diameter of this upstanding pad 34 is preferably less than that ofthe contact surface 40 of the rotor device. However, the diameter isalso preferably not less than a range of about 45% that of the rotordevice, such that the smaller diameter allows minute teetering of therotor device so that the rotor face and stator face will be in fullcontact therebetween. Accordingly, as will be described in greaterdetail below, the contact surface 40 of the rotor device 25 and seatingsurface 39 of the upstanding shaft pad 34 need not be in substantiallyflush contact with one another. In one specific embodiment, the diameterof the upstanding pad may be in the range of about 0.200″ to about0.368″, and more preferably about 0.230″, while the diameter of therotor device may be in the range of about 0.600″ to about 0.625″.

In a typical configuration, three strategically oriented dowel pins 37extend distally from the distal surface 38 of the head assembly 36(FIGS. 5-7). These dowel pins 37 are slideably received in correspondingthrough-holes 41 in the disk-shaped rotor device 25 that function tomount and align the rotor device 25 relative to the drive shaft 35.Furthermore, these dowel pins 37 enable torque transfer, and thus,rotation of the rotor device 25 as the drive shaft 35 is rotated aboutthe rotational axis.

The stator device 21 is mounted to a distal portion 42 of the housingassembly 33, via nuts 43, in a manner positioning the stator face 22 ofthe stator boss adjacent to and in contact with the rotor face 26 of therotor device 25. To generate the compressive force between the rotordevice 25 and the stator device 21, at the rotor-stator interface, thespring assembly 30 is cooperates between the housing assembly 33 and thehead assembly of the drive shaft 35. Briefly, a pressure adjuster nut 31is threadably mounted to the proximal portion of the housing assembly33. As the distal end of the pressure adjuster nut compresses a springstack (i.e., the stack of spring washers 32) against the head assembly36 the rotor device 25 is compressively urged against the stator boss27. Newer micro-fluidic valves have recently been developed thatincorporate pressure adjuster assemblies for ultra-high pressure fluidapplications that offer significant valve rebuild advantages. Theseassemblies are disclosed in our U.S. patent application Ser. No.12/815,265 to Tower et al, filed Jun. 14, 2010, entitled “REBUILDABLEMICRO-FLUIDIC VALVE ASSEMBLY”, which is incorporated by reference in itsentirety.

Referring now to FIGS. 3-7, and in accordance with the presentinvention, both the stator device 21 and the rotor device 25 arecomposed of a metallic material, forming a metal-on-metal stator-rotorinterface. The tribological coating (preferably a DLC) isolates truemetal-to-metal contact, of course, functioning to form a fluid-tightseal under higher pressure situations. As indicated above, forapplications greater than about 15 Kpsi, the stator face 22 ispreferably coated, while for applications ranging from about 3 Kpsi toless than about 6 Kpsi, either the stator face 22, the rotor face 26 orboth faces can be coated.

In this coated, metal-on-metal configuration, due to the rigidity andhardness of these shear face valve components, it is highly beneficialto orient the substantially planar faces of the stator device and therotor device substantially parallel to one another. However, while suchsubstantially parallel orientation is attainable, this may be costprohibitive, and thus not be practical. Due to the collective stack upof component tolerances, the metal rotor face 26 may not seal flatly orsubstantially parallel and flush to the substantially planar statorface, or the stator may not be perfectly planar in the first place.

Therefore, in accordance with another aspect of the present invention,the rotor assembly 29 incorporates a rotor face compliance assembly 45that cooperates with the substantially planar rotor face 26 to orient itsubstantially parallel to the stator face 22. The compliance assembly45, for example, includes a compliant element (e.g., a shim member 44 ofthe embodiment of FIGS. 5-8, or a support device 50 of the embodiment ofFIGS. 9-13) disposed between the head assembly 36 and the rotor device25 (or at least metallic or ceramic portion thereof, such as the rotorelement 46 of the embodiment of FIGS. 9-13) that is compressible in amanner enabling the substantially planar rotor face 26 to orientsubstantially parallel to the stator face 22. In one particularembodiment, as above-mentioned, the compliant element is provided by acompliant shim member 44 disposed between the distal seating surface 39of the raised platform 34 and the contact surface 40 of the rotorassembly 29. Hence, upon compression of the head assembly 36 against therotor device 25, and thus, compression of the rotor face against thestator face, the substantially more compliant shim 44 will be caused tocompress in a manner that seats the rotor face more flush and parallelagainst stator face. As mentioned above, thus, the need for a completelyflush seat between the contact surface 40 of the rotor device 25 and theseating surface 39 of the upstanding shaft pad 34 is not as necessary toensure a flush, sealed contact between the rotor face and the statorface.

The diameter of the shim member 44 is preferably less than that of thecontact surface 40 of the rotor device 25, but must incorporatethrough-holes 48 that are strategically aligned to receive and cooperatewith the dowel pins 37 that extend distally from the distal surface 38of the head assembly 36 (FIGS. 5-7). Similar to the rotor device 25,these dowel pins 37 are slideably received in the correspondingthrough-holes 48 in the shim 44 to mount, secure and align the shim 44relative to the head assembly 36.

As best shown in FIGS. 5, 7 and 8, the shim may be comprised of manydifferent shapes. For instance, the shim may be a conventional circularshape (FIG. 8), or may be an efficient, minute triangular shape (FIGS. 5and 7).

The material composition of the shim 44 should have sufficientstructural integrity to withstand the substantial compressive forcesapplied between the rotor device and the stator device. However, thematerial must also be sufficiently compliable to enable the rotor faceto seat substantially flush against the stator face, during operativecompression. The compressive modulus, k, for instance, is preferably inthe range of about 250 to about 300 kpsi. In one particular embodiment,the material composition of the shim 44 may be comprised of PolyethyleneTerephthalete Glycol (PETG) or Polyester or Polycarbonate, having athickness in the range of about 0.010″ to about 0.040″.

In another specific embodiment of the compliance assembly 45, asillustrated in FIGS. 9-12, the rotor device 25 is comprised of ametallic or ceramic (insertable) rotor element 46 that is received andsupported by a compliant support device 50. In this embodiment, thesupport device 50 functions as the compliant element, and thus, providesa compliant backing against the back side (i.e., the proximal face) ofthe inserted rotor element 46. FIGS. 10-12 best illustrate that themetallic rotor element 46 is preferably disk-shaped having the distalfacing, substantially planar rotor face 26 containing the rotor grooves47.

The support device 50 is for the most part is shaped similar to atypical rotor device 25, such as that in the embodiment of FIGS. 5-7.The distal face of the support device, however, defines a receivingsocket 51 with a peripheral interior sidewall 52 formed and dimensionedfor press-fit receipt of the outer circumferential or peripheral wall 53of the rotor element 46 until a proximal face 54 thereof contacts and issupported by the distal socket face 55 of the receiving socket 51.

By providing a compliant backing material, at least in the axialdirection, upon the application of a compressive force between the rotordevice 25 and the stator face 22, the contacting surfaces of the supportdevice 50 should have some compliance or compression. Such compressivecompliance allows the substantially planar rotor face 26 to slightlyrelocate to an orientation that is substantially parallel to thesubstantially planar stator face. In other words, the compliant materialwill “move” or compress, due to contact with the backside contactsurface of the metal rotor element, allowing the polymer to absorb anymisalignment between the rotor face and the stator face of the statorboss. The rotor face 26 can then seal and mate flat against andsubstantially parallel to the stator boss face 22.

In one specific embodiment, the support device 50 is preferably about0.100″ to about 0.200″ thick, has a compressive modulus, k, in the rangeof about 4000 to about 5000 kpsi, and is composed of a polymer materialexhibiting high tensile and compressive strength. Such a compliantmaterial exhibiting these other properties, permits minute compliance,while further permitting transfer of the high compressive forces in theaxial direction to the rotor face 26 of the rotor element 46. As bestillustrated in FIGS. 13 and 14, compliance on the order of about 1° orabout 0.005″ at the circumferential edges of the rotor element isattainable.

The polymer material used can be changed for a variety of applications.Depending upon whether the application is for the lower region of whatis considered a high lower pressure application (e.g., 3-6 Kpsi), asofter unfilled polymer, such as PEEK™ or Nylon, may be applied. Incontrast, for higher pressure applications (e.g., 15-25 Kpsi), a carbonfilled polymer material may be necessary which significantly increasesthe polymers tensile and compressive strength.

One such high strength polymer support material is an engineered blendof PEEK™ with carbon fibers (e.g., a 20%-30% carbon PEEK™ blend). Thispolymer material is carbon filled, yielding the requisite high tensileand compressive strength. Thus, due to the high pressures of the springwashers 32 needed to seal the valve, this PEEK™ blend is currently thepreferred material. It will be appreciated, however, that other polymerbased materials, or even a higher strength elastomer could be used.

Turning now to FIGS. 10 and 11, the disk-shaped rotor element 46 isgenerally keyed. Not only does this aligned the rotor face 26 relativeto the drive shaft 35, but also functions to facilitate torque transferto the rotor element during the rotation of the support device 50. Forease of machining, the rotor element 46 is “D” shaped and the femalereceiving socket 51 is a modified “D” shape where the corners of theflat have been relieved for the radius of an end mill. The two parts areassembled by using an arbor press. The arbor press press-fits (0.002″press fit) the two parts together. It will be appreciated, of course,that the outer peripheral edges may be any shape that enables the metalseal insert to press-fit into the polymer backing.

Referring now the embodiment of FIGS. 16-24, the rotor assembly 29incorporates an alternative embodiment rotor face compliance assembly 45that enables the rotor face to “rock” and/or “pivot” to an orientationthat allows the opposed rotor face and stator face to seal and mateflushly against one another on the stator boss 27.

In this configuration, in a simplified description, a disk-shapedmetallic rotor element 60 (similar to that provided the embodiment ofFIGS. 16 and 20-23) is pivotally seated atop a ball bearing 61, which inturn, is seated atop a distal end of the head assembly 36 of the driveshaft 35. Accordingly, as a compressive force is applied to the driveshaft 35, the force is transferred, via the ball bearing 61, to therotor element 60. Upon increasing pressure between the adjacent, andopposed contact, at the rotor/stator interface, the rotor element 60 iscaused to minutely rock or pivot in an effort to reorient and align therotor face substantially parallel to the stator face.

To facilitate support of the pivoting rotor element 60, a drive ring 62is provided that is also shaped similar to the conventional rotor deviceit replaces. FIGS. 16 and 17 best illustrate that this drive ringincludes an axially extending receiving aperture 63 formed for axialreceipt of the rotor element 60 in a manner allowing the insert to“float” axially therein, while at the same time securing the rotorelement rotationally to the drive ring 62 for rotation about therotational axis.

Accordingly, the inner diameter of the inner sidewall 66 that definesthe receiving aperture 63 is slightly larger than the diameter of theouter circumferential wall 67 of the rotor element 60 to permit minutepivotal movement thereof. The clearance, for example, between the outerdiameter of the seal insert and the inner diameter of the drive ring isabout 0.020″ (0.010″ per side). This allows the seal insert to movelaterally back and forth within the ring drive 0.010″ per side.

To provide seating support atop the ball bearing 61, the proximal facingsurface of the rotor element 60 includes a dome-shaped ball socket 68that is formed, sized and dimensioned to receive a portion of the ballbearing. This configuration is further responsible for providing thepivotal support about ball bearing, and relative to the drive ring 62.

To transfer torque to the axially free floating rotor element 60, as thedrive ring 62 rotates about the drive shaft axis, a plurality of guidepins 70 extend radially into the aperture 63 from the inner sidewall 66of the drive ring 62. These radial guide pins 70 are formed for slidingaxial receipt in corresponding elongated receiving slots 71 extending inan axial direction along the outer circumferential wall 67 of the rotorelement. Accordingly, as the drive ring is rotated, the guide pins 70transfer this rotational motion directly to the rotor element.

For precise and accurate rotational displacement and movement of therotor element, the tolerances between the diameter of the guide pins 70and the width of the corresponding receiving slots should therefore berelatively small. In one specific embodiment, for example, the tolerancebetween the diameter of guide pins and the width of the slots isapproximately 0.002″ (0.001″ per side). For instance, if the diameter ofthe guide pin is selected to be about 0.029″-0.031″, then the width ofthe guide slot 71 in the rotor element should be selected to be in therange of about seal is 0.031″-0.033″. Such a relatively small tolerancewill enable substantially immediate transfer of the rotation of thedrive ring 62, about the drive shaft axis, directly to the rotor element60. The relative position of the rotor seal grooves 47 relative to thestator ports 23 can therefore be accurately determined.

These radially spaced guide slots 71, however, also extend radially intothe outer circumferential wall 67 of the rotor element by a depthslightly greater than the radial length of the guide pins 70. Thistolerance permits guide pins 70 to extend slightly into and out of thecorresponding guide slots to enable the aforementioned minute lateralmovement (on the order of about 0.010″ per side) of the rotor devicewithin the drive ring receiving aperture 63. Hence, as the rotor element60 minutely pivots or rolls about the ball bearing, it also slides alongthe guide pins 70. This relative axial movement (as well as very minute,relative radial movement) of the guide pins 70 axially along thecorresponding receiving slots 71, while also moving minutely laterallywithin the receiving aperture, enabling the substantially planar rotorface 26 to slightly reorient substantially parallel to the stator face22. Thus, unlike the polymer backed support device 50 of the embodimentsof FIGS. 18-21, the compliance from this pivotal embodiment is providedby the ability of the rotor element seal insert to “move” and “pivot”(i.e., roll) about the ball bearing until the rotor face is reorientedsubstantially parallel to, and substantially flat against the statorface 22 of the stator boss 27.

These guide pins 70 can be provided by threaded screws (as shown andillustrated) or can be molded or milled during formation of the drivering 62. Moreover, while five guide pins 70 are shown radially spacedabout the inner sidewall 66 of the receiving aperture 63, the complianceassembly 45 could function with only one guide pin and correspondingslot (albeit a more limited compliance). A minimum of three radiallyspaced guide pins and corresponding guide slots, however, are desired toprovide an increased scope of compliance.

An opposed domed-shape socket 72 is also defined by the distal face ofthe head assembly 36 that is formed to similarly seat against the ballbearing 61. Preferably, this opposed domed-shape socket 72 is providedby an insertable dowel pin 73, press-fit into a corresponding passage 75at the distal end of the drive shaft 35.

Referring now to FIGS. 18 and 19, as a compression force, via springassembly 30, axially urges the drive shaft 35 toward the stator device21, the dowel pin 73 compresses the ball bearing 61. In turn, the ballbearing 61 transfers this axial compressive force to the rotor element60 to form the fluid-tight seal at the rotor-stator interface.

It will be appreciated that, in order to accommodate the highcompressive forces applied to the ball bearing, the diameter of the ballbearing should be at least about ½ (and preferably ⅔) the diameter ofthe rotor element 60. This assures that the compressive forces will bemore widely distributed about the domed-shaped socket 68 of the rotorelement, as compared to a more concentrated force distribution shouldthe ball bearing be of a smaller diameter.

Although the present invention has been primarily described as applyingto shear face valves for high pressure applications that require highlifecycle capabilities (e.g., such as all HPLC Instrumentplatforms/designs), it will be appreciated that this technology may beapplied to all shear valve platforms/designs (such as AI (analyticalchemistry) and IVD (In-vitro Diagnostics)).

Furthermore, while the present invention has been described inconnection with the preferred form of practicing it and modificationsthereto, those of ordinary skill in the art will understand that manyother modifications can be made thereto within the scope of the claimsthat follow. Accordingly, it is not intended that the scope of theinvention in any way be limited by the above description, but instead bedetermined entirely by reference to the claims that follow.

1. A rotary shear valve assembly comprising: a stator device defining asubstantially planar stator face and at least two or more statorchannels in fluid communication with said stator face at correspondingstator ports, said stator face being composed substantially of one ametallic material and a ceramic material; a rotor device having asubstantially planar rotor face defining one or more rotor channels,said rotor face being composed substantially of one a metallic materialand a ceramic material; and a tribological coating disposed atop atleast one of said rotor face and said stator face, wherein said rotordevice is rotatably mounted about a rotational axis in a manner enablingfluid-tight, selective relative rotation between the rotor face and thestator face, at a rotor-stator interface, between two or more rotorpositions.
 2. The valve assembly according to claim 1, wherein saidtribological coating is a Diamond Like Coating (DLC).
 3. The valveassembly according to claim 1, wherein said tribological coating isdisposed atop said stator face.
 4. The valve assembly according to claim3, wherein said rotor face and said stator face are both comprised of asubstantially metallic material.
 5. The valve assembly according toclaim 1, wherein said metallic material of said rotor face and saidstator face is comprised of one of steel and titanium.
 6. The valveassembly according to claim 5, wherein said tribological coating isdisposed atop said stator face.
 7. The valve assembly according to claim6, wherein said tribological coating is a Diamond Like Coating (DLC). 8.The valve assembly according to claim 1, wherein said stator device andsaid rotor device are compressed together in a manner creating acompression pressure at the rotor-stator interface in the range of about3 Kpsi to about 25 Kpsi.
 9. The valve assembly according to claim 1,further including: a compliance assembly cooperating with the rotordevice in a manner orienting the substantially planar rotor facesubstantially parallel to and substantially flush against thesubstantially planar stator face of the stator device.
 10. The valveassembly according to claim 9, wherein said rotor device defining aproximal facing contact surface oriented opposite said rotor face, andsaid compliance assembly including a compliant element in supportiveabutting contact with the contact surface of said rotor device.
 11. Thevalve assembly according to claim 10, further including: a rotorassembly including a valve shaft, configured for rotation about arotational axis of the valve assembly, and a head portion disposed at adistal end of said valve shaft, said head portion defining a distalseating surface configured to seat the rotor device thereon, and saidcompliant element defining a proximal facing surface oriented oppositesaid contact surface, and disposed between, and in abutting contactwith, the contact surface of said rotor device and the distal seatingsurface of said head portion.
 12. The valve assembly according to claim11, wherein said compliant element comprising a relatively thin shimmember having a compressive modulus, k, in the range of about 250 toabout 300 kpsi.
 13. The valve assembly according to claim 11, whereinsaid head portion having a shaft pad, defining said seating surface,distally extending from a distal surface of said head portion.
 14. Thevalve assembly according to claim 11, wherein said compliant elementdefining a receiving socket, a bottom portion of which is defined bysaid seating surface, and formed and dimensioned for aligned, slidingaxial receipt of a rotor element of the rotor device therein.
 15. Thevalve assembly according to claim 14, wherein said receiving socketfurther defined by an interior sidewall, formed and dimensioned forpress-fit receipt and contact with an outer circumferential wall of saidrotor element.
 16. The valve assembly according to claim 15, whereinsaid interior sidewall and the rotor outer circumferential wallcooperate for keyed alignment therebetween.
 17. The valve assemblyaccording to claim 16, wherein said interior sidewall and the rotorouter circumferential wall are D-shaped.
 18. The valve assemblyaccording to claim 9, further including a rotor assembly including avalve shaft, configured for rotation about a rotational axis of thevalve assembly, and a head portion disposed at a distal end of saidvalve shaft, said head portion defining a distal seating surfaceconfigured to seat a metallic rotor element of the rotor device thereon,and said compliance assembly including a ball bearing member disposedbetween said head portion of said rotor assembly and said rotor element,enabling minute compliant pivotal motion of said rotor face about saidball bearing member.
 19. The valve assembly according to claim 18,wherein said head portion having a distal seating surface that defines adome-shaped socket formed and dimensioned for receipt of a portion saidball bearing member therein, and said rotor element having a proximalfacing contact surface oriented opposite said rotor face, said contactsurface defining a dome-shaped ball socket formed and dimensioned forpivotal receipt of another portion said ball bearing member therein. 20.The valve assembly according to claim 19, wherein said complianceassembly further including a drive ring disposed adjacent said seatingsurface of said head portion, and having an interior wall defining acentral through-passage formed and dimensioned for axial sliding receiptof said rotor element therein in a manner enabling minute pivotalmovement atop said ball bearing member.
 21. The valve assembly accordingto claim 20, wherein said compliance assembly further includes analignment structure configured for aligned cooperation between saidrotor element and drive ring.
 22. A rotary shear valve assemblycomprising: a stator device defining a substantially planar stator faceand at least two or more stator channels in fluid communication withstator face at corresponding stator ports, said stator face beingcomposed substantially of one of a metallic material and a ceramicmaterial; a rotor assembly having a rotor device having a substantiallyplanar rotor face, said rotor device being rotatably mounted about arotational axis, said rotor face being composed substantially of one ametallic material and a ceramic material; and a compliance assemblycooperating with the rotor element in a manner orienting thesubstantially planar rotor face substantially parallel to andsubstantially flush against the substantially planar stator face of thestator device for fluid-tight, selective relative rotation between therotor face and the stator face, at a rotor-stator interface, at two ormore rotor positions.
 23. The valve assembly according to claim 22,wherein said rotor device defining a proximal facing contact surfaceoriented opposite said rotor face, and said compliance assemblyincluding a compliant element in supportive abutting contact with thecontact surface of said rotor device.
 24. The valve assembly accordingto claim 23, wherein said rotor assembly including a valve shaft,configured for rotation about a rotational axis of the valve assembly,and a head portion disposed at a distal end of said valve shaft, saidhead portion defining a distal seating surface, and said compliantelement defining a proximal facing surface oriented opposite saidcontact surface, and disposed between, and in abutting contact with, thecontact surface of said rotor device and the distal seating surface ofsaid head portion.
 25. The valve assembly according to claim 24, whereinsaid compliant element comprising a relatively thin shim member having acompressive modulus, k, in the range of about 250 to about 300 kpsi. 26.The valve assembly according to claim 25, wherein said shim member iscomprised of one of Polyethylene Terephthalete Glycol (PETG) andPolyester or Polycarbonate.
 27. The valve assembly according to claim26, wherein a thickness of said shim member is in the range of about0.010″ to about 0.040″.
 28. The valve assembly according to claim 24,wherein said head portion having a shaft pad, defining said seatingsurface, distally extending from a distal surface of said head portion.29. The valve assembly according to claim 24, wherein said rotor faceand said stator face are both comprised of a substantially metallicmaterial.
 30. The valve assembly according to claim 24, wherein eachsaid stator device and said rotor device is comprised of one of steeland titanium.
 31. The valve assembly according to claim 24, wherein saidcompliant element defining a receiving socket, a bottom portion of whichis defined by said seating surface, and formed and dimensioned foraligned, sliding axial receipt of said rotor element therein.
 32. Thevalve assembly according to claim 31, wherein said receiving socketfurther defined by an interior sidewall, formed and dimensioned forpress-fit receipt and contact with an outer circumferential wall of saidrotor element.
 33. The valve assembly according to claim 32, whereinsaid interior sidewall and the rotor outer circumferential wallcooperate for keyed alignment therebetween.
 34. The valve assemblyaccording to claim 33, wherein said interior sidewall and the rotorouter circumferential wall are D-shaped.
 35. The valve assemblyaccording to claim 31, wherein said compliant element having acompressive modulus, k, in the range of about 4000 to about 5000 kpsi.36. The valve assembly according to claim 35, wherein said compliantelement being comprised of one of a softer unfilled polymer material anda carbon filled polymer material.
 37. The valve assembly according toclaim 36, wherein said compliant element is comprised of one of a PEEK™material, a nylon material and a 20%-30% carbon PEEK™ blend.
 38. Thevalve assembly according to claim 37, wherein a thickness of saidcompliant element is in the range of about 0.100″ to about 0.200″. 39.The valve assembly according to claim 21, wherein said rotor assemblyincluding a valve shaft, configured for rotation about a rotational axisof the valve assembly, and a head portion disposed at a distal end ofsaid valve shaft, said head portion defining a distal seating surfaceconfigured to seat a metallic rotor element of the rotor device thereon,and said compliance assembly including a ball bearing member disposedbetween said head portion of said rotor assembly and said rotor element,enabling minute compliant pivotal motion of said rotor face about saidball bearing member.
 40. The valve assembly according to claim 39,wherein said head portion having a distal seating surface that defines adome-shaped socket formed and dimensioned for receipt of a portion saidball bearing member therein, and said rotor element having a proximalfacing contact surface oriented opposite said rotor face, said contactsurface defining a dome-shaped ball socket formed and dimensioned forpivotal receipt of another portion said ball bearing member therein. 41.The valve assembly according to claim 40, wherein said complianceassembly further including a drive ring disposed adjacent said seatingsurface of said head portion, and having an interior wall defining acentral through-passage formed and dimensioned for axial sliding receiptof said rotor element therein in a manner enabling minute pivotalmovement atop said ball bearing member.
 42. The valve assembly accordingto claim 41, wherein said compliance assembly further includes analignment structure configured for aligned cooperation between saidrotor element and drive ring.
 43. The valve assembly according to claim42, wherein said rotor element having a substantially cylindricalsidewall extending between said rotor face and said contact surface,said sidewall defining two or more elongated receiving slots orientedsubstantially parallel to said rotational axis, and axially extendingfrom about a central portion of said sidewall to said contact surface,and said alignment structure including two or more corresponding guidepins extending radially inward from said interior wall of said drivering, said guide pins being sized and dimensioned for sliding axialreceipt in a corresponding receiving slot.